Water-containing dry cleaning compositions

ABSTRACT

Combinations of surface active materials which solubilize significant quantities of water in dry cleaning solvents, the combination comprising from 70 to 90 percent by weight of a dialkyl benzene sulfonate in which the alkyl groups are substantially linear and contain from six to 10 carbon atoms and from 10 to 30 percent by weight of a C15 20 branched chain monoalkyl benzene sulfonate.

United States Patent Straus [151 3,655,572 14 1 Apr. 11, 1972 [54] WATER-CONTAINING DRY CLEANING COMPOSITIONS [72] Inventor: Alan E. Straus, El Cerrito, Calif.

[73] Assignee: Chevron Research Company, San Francisco, Calif.

[22] Filed: Jan. 21, 1970 [21] Appl. No.: 4,736

[52] U.S. Cl ..252/171, 8/142, 252/558 [51] Int. Cl ..C09d 9/04, Cl 1d 7/50, C23g 5/02 [58] Field ofSearch ..252/171, 161, 170, 558; 8/142 [56] References Cited UNITED STATES PATENTS 2,388,962 11/1945 Flett ..252/161 2,712,530 7/1955 Baumgartner ..252/161 2,956,026 10/1960 Lew .252/ 161 3,311,563 3/1967 McEwen .252/161 3,310,498 3/1967 Michaels et a1 ..8/142 3,310,499 3/ 1967 Michaels et a1 ..8/ 142 Primary Examiner-Leon D. Rosdol Assistant Examiner-W. Schulz Attorney-A. L. Snow, F. E. Johnston, G. F. Magdeburger, John Stoner, Jr. and J. T. Brooks [57] ABSTRACT 10 Claims, No Drawings WATER-CONTAINING DRY CLEANING COMPOSITIONS BACKGROUND OF THE INVENTION The present invention relates to dry cleaning compositions and more particularly it relates to compositions which have therein solubilized significant quantities of water, the solubilization being effected by novel combinations of monoalkyl and dialkyl benzene sulfonates.

In the dry cleaning art it is common practice to employ a solvent for cleaning the soiled fabrics. The solvents which act to remove the oil-base stains are usually materials such as Stoddard solvent, which is the white spirits fractions of petroleum, or a halogenated hydrocarbonsolvent such as perchloroethylene. While these materials are effective in removing the oil-base stains, they are ineffective in removing water-soluble fabric stains. Therefore, it has been common practice to add water to the solvent and effect the solubilization of the water in the dry cleaning solvent with various surface active additives such as alkylbenzene sulfonates and poly oxy alkyl ether of alkylphenols, etc.

In addition to their emulsifying or solubilizing action, the surface active materials, or course, act as dispersants or detergents for the soil. The use of these materials thus enables the cleaner to effectively remove the water-soluble stains during the wash wheel treatment of the clothes, reduces the amount of prespotting that is necessary, and dispenses with the need for a wet cleaning step (water wash) of the garments.

The advantages of maximum water content in the dry cleaning fluid are stated succinctly in an article by Fulton, Alexander, Lloyd and Schwartz, Detergents in Dry Cleaning, ASTM Bulletin TD 153, 63, Sept. 1953, at page 68 wherein it is stated tha one way of increasing water-soluble soil removal is to increase the solubilization of water.

It is thus desirable that the maximum quantity of water possible be either solubilized or emulsified in the solvent. In the past the commonly used surface active materials have been only effective in solubilizing a maximum of about 1 percent by weight of water in the Stoddard solvent and a somewhat lesser quantity (e.g. 0.5 percent) in perchloroethylene.

SUMMARY OF THE INVENTION Synergistic combinations of surface active materials are provided. These combinations, employed in minor amounts, effect the solubilization of significant quantities of water in hydrocarbon solvents and in halogenated hydrocarbon solvents. The synergistic combinations comprise from about 5 to 45 percent by weight of a monoalkyl benzene sulfonate in which the alkyl group has substantial branching and contains from about to 22 carbon atoms and from about 55 to 95 percent by weight of a dialkyl benzene sulfonate in which the alkyl groups are substantially linear and contain from about six to 12 carbon atoms.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The compositions which are particularly effective comprise a fraction of di-C C linear alkylbenzene sulfonates with a minor amount of a C,,,---C branched chain secondary monoalkylbenzene sulfonate. The dialkyl material preferably will have linear alkyl groups of from seven to nine carbon atoms. The preferred range of dialkyl benzene sulfonate concentration will be from about 70 to 90 percent by weight.

When the combinations are employed in dry cleaning solvents, they are present in amounts of from about 0.1 to 5.0 percent by weight relative to the total composition.

The dialkylbenzene materials are straight chain substituted and are prepared by conventional alkylation techniques. Thus, in a preferred embodiment the compounds are prepared by alkylation of benzene with alpha-olefin fractions derived from the cracking of petroleum waxes. The alkylation is preferably achieved with hydrogen fluoride catalyst, although Friedel- Craft catalysts such as aluminum chloride, etc., may also be employed. After alkylation with a suitable catalyst employing an excess of the olefin, the monoalkyl material may be removed by distillation. More usually the dialkyl material will be the by-product of monoalkyl benzene production.

The monoalkylbenzene material is prepared by similar techniques, employing, however, highly branched olefins such as the propylene polymers. The preferred material is derived from a propylene hexamer. Thus, alkylation with linear olefins of from 15 to 24 carbon atoms gives a suitable product. The preferred monoalkylbenzenes will contain from about 16 to 20 atoms in the alkyl group.

The sulfonation of both the mono and dialkyl materials may be achieved by conventional sulfonation methods-for example, with oleum, sulfur trioxide, or chloro sulfonic acid. The sulfonation is preferably achieved with sulfur trioxide in a falling film apparatus.

The sulfonic acid produced in the sulfonation will be neutralized with a base to provide the sulfonate salts employed in the invention. Bases providing water-soluble cations will be suitable. Thus, effective water-soluble cations include alkali metal, alkaline earth metal, ammonium and various organic cations such as tertiary amino cations. Examples of the alkali metal include lithium, sodium, and potassium ions. Examples of suitable alkaline earth metal cations include magnesium, calcium, strontium, cadmium and barium. Examples of suitable amino cations include those of the following structure:

NH (CH CH;,) or NH (CH CH 0H) Generally the alkali metal cations are preferred, and most particularly sodium ion is preferred.

The dry cleaning solvents which may be employed in the compositions of this invention are conventional materials such as light hydrocarbons and chlorinated hydrocarbons.

The chlorinated hydrocarbons employed are usually those of lower molecular weight exemplified by carbon tetrachloride, trichloroethylene, perchloroethylene, etc. Perchloroethylene is most commonly used.

The combinations of sulfonates of the invention are employed in the dry cleaning compositions in amounts sufiicient to solubilize the maximum amount of water possible. Thus, in a typical composition having Stoddard solvent as the base fluid, the sulfonates will usually be used in amounts of from 0.5 to 5 percent by weight relative to the total weight of cleaning composition. As will be demonstrated, a combination falling within this weight range (e.g., 1 percent by weight) will solubilize up to 2.5 percent by weight of water. Greater concentrations of the surface-active combination will solubilize up to about 5 percent water.

When the combinations of sulfonates are employed as solubilizing agents in the dry cleaning fluids they may be compounded with water and prepared as stock solutions which may be added to the dry-cleaning solvent when necessary during the cleaning process. Thus, the emulsion may be added directly to the solvent in the wash wheel in order to maintain a maximum concentration of water in the cleaning composition.

EXAMPLE I In order to demonstrate the effectiveness of the sulfonate combinations in solubilizing water in dry-cleaning solvents various blends of a sodium dialkylbenzene sulfonate having an average of seven to nine carbon atoms in each alkyl group and in which the alkyl groups were straight chain and a sodium monoalkyl benzene sulfonate having an average of 18 atoms in.

the alkyl group which was derived from a hexapropylene were combined in various ratios and added to dry-cleaning solvents at a concentration of 1% by weight. Water was added to the solution and the percent by weight of water solubilized in the solvent was determined. The solvents employed were normal Stoddard solvent and perchloroethylene. Stoddard solvent, which is the most commonly used hydrocarbon dry-cleaning fluid, is defined as follows: A petroleum distillate characterized by a flash point of not lower than F. (Tag. closed cup test) and distilling over to not less than 50 percent at 350 F. with the end point being not higher than 410 F. It has den- TABLE H O Solubilization by Dialkylbenzene Sulfonate/ Monoalkylbenzene Sulfonate Combination H,O Solubilization Dialkylbenzene Monoalkylbenzene Wt Sulfonate Sulfonate Stoddard Perchlora- Wt in solvent Wt in solvent Solvent ethylene As may be seen from these data, whereas the dialkylbenzene sulfonate along solubilized l.l% by weight of water and a 60/40 (Wt. percent) blend of dialkyl and monoalkyl materials solubilized less than 0.1 percent, in Stoddard solvent the 80/20 combination solubilized 2.5 percent. This combination thus is remarkably more effective than conventional solubilizing or emulsifying agents in maintaining a significant water content in the solvent. It may also be noted that the 70/30 combination in perchloroethylene increased the water content to 0.8 percent, a significant increase over that achieved with either the dialkyl or monoalkyl materials alone.

Tests performed with straight chain monoolefins replacing the branched chain monoolefins showed that the resulting combinations were completely ineffective in solubilizing water in the dry cleaning solvents.

While the character of this invention has been described in detail with numerous examples, this has been done by way of illustration only and without limitation of the invention. It will be apparent to those skilled in the art that modifications and variations of the illustrative example may be made in the practice of the invention within the scope of the following claims.

I claim:

1. A combination of surface active materials capable of solubilizing significant quantities of water in hydrocarbon or chlorinated hydrocarbon solvents, said combination consisting essentially of a. from 55 to 95 percent by weight of a dialkyl benzene sulfonate in which the alkyl groups are substantially linear and each contain from about six to 12 carbon atoms, and

b. from 5 to 45 percent by weight of a monoalkyl benzene sulfonate in which the alkyl group has substantial branching and contains from about 15 to 22 carbon atoms, said sulfonate containing water-soluble cations.

2. The combination of claim 1 in which the concentration of (a) is from about 70 to percent by weight and that of (b) from 10 to 30 percent by weight.

3. The combination of claim 1 in which the alkyl groups of (a) contain from seven to nine carbon atoms.

4. The combination of claim 2 in which the alkyl groups of (a) are derived from alpha olefins.

5. The combination of claim 2 in which the alkyl group of (b) is derived from polymerized propylene.

6. A dry cleaning composition consisting essentially of a major portion of a dry cleaning fluid, a minor portion of water sufiicient to effect removal of water-soluble stains from fabric,

and a min or portion, from 0.1 to 5.0 ercent by weight of the combination of surface active materi s of claim 1 to solubllize said minor portion of water in the dry cleaning fluid.

7. The composition of claim 6 wherein the water is present in an amount of from 0.1 to 5.0 percent by weight.

8. The composition of claim 7 wherein the combination of surface active materials is present in an amount of from 0.1 to 5 .0 percent by weight.

9. The composition of claim 6 in which the dry cleaning fluid is Stoddard solvent.

10. The composition of claim 6 in which the dry cleaning fluid is perchloroethylene. 

2. The combination of claim 1 in which the concentration of (a) is from about 70 to 90 percent by weight and that of (b) from 10 to 30 percent by weight.
 3. The combination of claim 1 in which the alkyl groups of (a) contain from seven to nine carbon atoms.
 4. The combination of claim 2 in which the alkyl groups of (a) are derived from alpha olefins.
 5. The combination of claim 2 in which the alkyl group of (b) is derived from polymerized propylene.
 6. A dry cleaning composition consisting essentially of a major portion of a dry cleaning fluid, a minor portion of water sufficient to effect removal of water-soluble stains from fabric, and a minor portion, from 0.1 to 5.0 percent by weight of the combination of surface active materials of claim 1 to solubilize said minor portion of water in the dry cleaning fluid.
 7. The composition of claim 6 wherein the water is present in an amount of from 0.1 to 5.0 percent by weight.
 8. The composition of claim 7 wherein the combination of surface active materials is present in an amount of from 0.1 to 5.0 percent by weight.
 9. The composition of claim 6 in which the dry cleaning fluid is Stoddard solvent.
 10. The composition of claim 6 in which the dry cleaning fluid is perchloroethylene. 